/*
 * Copyright 2010-2020 Alfresco Software, Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.activiti.engine.impl.bpmn.behavior;

import java.util.Objects;

import org.activiti.engine.ActivitiException;
import org.activiti.engine.DynamicBpmnConstants;
import org.activiti.engine.delegate.BpmnError;
import org.activiti.engine.delegate.DelegateExecution;
import org.activiti.engine.delegate.Expression;
import org.activiti.engine.impl.bpmn.helper.ErrorPropagation;
import org.activiti.engine.impl.bpmn.helper.SkipExpressionUtil;
import org.activiti.engine.impl.context.Context;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.fasterxml.jackson.databind.node.ObjectNode;
import com.ziroom.common.api.constants.Constant;
import com.ziroom.common.api.constants.ErrorConstant;
import com.ziroom.common.api.constants.LogConstant;
import com.ziroom.common.api.exception.lock.AddLockException;
import com.ziroom.common.api.exception.lock.AddLockInterruptException;
import com.ziroom.common.api.exception.workflow.WorkflowBusinessException;

/**
 * ActivityBehavior that evaluates an expression when executed. Optionally, it
 * sets the result of the expression as a variable on the execution.
 *
 */
public class ServiceTaskExpressionActivityBehavior extends TaskActivityBehavior {

	private static final long serialVersionUID = 1L;
	private static Logger logger = LoggerFactory.getLogger(ServiceTaskExpressionActivityBehavior.class);

	protected String serviceTaskId;
	protected Expression expression;
	protected Expression skipExpression;
	protected String resultVariable;

	public ServiceTaskExpressionActivityBehavior(String serviceTaskId, Expression expression, Expression skipExpression, String resultVariable) {
		this.serviceTaskId = serviceTaskId;
		this.expression = expression;
		this.skipExpression = skipExpression;
		this.resultVariable = resultVariable;
	}

	@Override
	public void execute(DelegateExecution execution) {
		Object value = null;
		try {
			boolean isSkipExpressionEnabled = SkipExpressionUtil.isSkipExpressionEnabled(execution, skipExpression);
			if (!isSkipExpressionEnabled || (isSkipExpressionEnabled && !SkipExpressionUtil.shouldSkipFlowElement(execution, skipExpression))) {
				if (Context.getProcessEngineConfiguration().isEnableProcessDefinitionInfoCache()) {
					ObjectNode taskElementProperties = Context.getBpmnOverrideElementProperties(serviceTaskId, execution.getProcessDefinitionId());
					if (taskElementProperties != null && taskElementProperties.has(DynamicBpmnConstants.SERVICE_TASK_EXPRESSION)) {
						String overrideExpression = taskElementProperties.get(DynamicBpmnConstants.SERVICE_TASK_EXPRESSION).asText();
						if (StringUtils.isNotEmpty(overrideExpression) && !overrideExpression.equals(expression.getExpressionText())) {
							expression = Context.getProcessEngineConfiguration().getExpressionManager().createExpression(overrideExpression);
						}
					}
				}
				
				try {
					//System.out.println("=====开始buz：" + System.currentTimeMillis());
					value = expression.getValue(execution);
					//System.out.println("=====结束buz：" + System.currentTimeMillis());
				} catch (Throwable exc) {
					Throwable cause = exc;
					while (cause.getCause() != null) {
						cause = cause.getCause();
					}
					// 只要是未捕获异常，除了WorkflowBusinessException外，一律抛出
					if(cause instanceof WorkflowBusinessException){
						// 如果是WorkflowBusinessException异常，则不再继续抛出，直接保存一个名为"ex"的变量
						execution.setTransientVariable(Constant.WORKFLOWBUSINESSEXCEPTION_KEY, cause);
					}else if(cause instanceof AddLockInterruptException || cause instanceof AddLockException){
						// 如果是加锁失败，记录ex属性，同时抛出异常，这个异常会被上层捕获并忽略
						execution.setTransientVariable(Constant.WORKFLOWBUSINESSEXCEPTION_KEY, new WorkflowBusinessException(ErrorConstant.WORKFLOW_INSECT_PREVENTION_CODE, ErrorConstant.WORKFLOW_INSECT_PREVENTION_MSG));
						throw new AddLockInterruptException(cause.getMessage(), cause);
					}else{
						throw new ActivitiException("Could not execute service task expression", exc);
					}
				}
				logger.info(LogConstant.WORKFLOW + " expression {} execute result: {}", expression, Objects.toString(value));
				if (resultVariable != null) {
					// 一般设置到parent
					execution.setTransientVariable(resultVariable, value);
				}
			}

			leave(execution);
		} catch (Exception exc) {
			Throwable cause = exc;
			BpmnError error = null;
			while (cause != null) {
				if (cause instanceof BpmnError) {
					error = (BpmnError) cause;
					break;
				}
				cause = cause.getCause();
			}

			if (error != null) {
				ErrorPropagation.propagateError(error, execution);
			} else if (exc instanceof AddLockInterruptException) {
				// 如果是加锁失败，抛出异常，这个异常会被上层捕获并忽略
				throw exc;
	        } else {
				throw new ActivitiException("Could not execute service task expression", exc);
			}
		}
	}

}
